基于COMSOL有限元法的涡流探头线圈仿真  

Simulation of Eddy Current Probe Coil Based on COMSOL Finite Element Method

作　　者：邱建东 祁育栋 许向东 QIU Jian-dong;QI Yu-dong;XU Xiang-dong(School of Mechanical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)

机构地区：[1]兰州交通大学机电工程学院,兰州730070

出　　处：《兰州交通大学学报》2021年第5期65-71,共7页Journal of Lanzhou Jiaotong University

基　　金：国家自然科学基金项目(71961015);兰州交通大学2020年“金课”建设(培育)项目。

摘　　要：为了研究涡流检测过程中激励频率、提离和线圈几何尺寸(外径、内径、高度)对涡流探头电磁特性的影响,以涡流检测原理为基础,采用COMSOL软件建立了不同的探头线圈模型,仿真分析了不同参数下探头周围磁场的分布及试件中涡流的分布情况,结合探头线圈中阻抗变化来判断探头检测性能.仿真结果表明:涡流探头的阻抗随着探头线圈内径和外径的增大而增大,随着探头线圈高度的减小而增大,当探头线圈内径和外径增大、高度减小时,探头线圈的实部和虚部均增大,探头灵敏度提高;此外,从影响探头性能的源头分析了激励频率及提离大小对涡流探头灵敏度的影响规律,并对仿真结果和已有理论分析结果进行了对比验证.所得结论可为合理确定激励频率和提离提供一定的参考依据,同时可为探头结构的优化设计提供理论指导.To study the influence of excitation frequency,lift-off distance and coil geometry size(outer radius,inner radius,height)on the electromagnetic characteristics of eddy current probe in the process of eddy current testing,different coil models were established by COMSOL finite element simulation software based on the principle of eddy current testing.The distribution of magnetic field around the probe and eddy current in the specimen under different parameters were simulated and analyzed,and the detection performance of the probe was judged by the change of impedance in the probe coil.The simulation results show that the impedance of the eddy current probe rises with the increase of the inner and outer radius of the probe coil and the decrease of the height.The larger the inner and outer radius and the lower the height are,the higher the sensitivity of the eddy current probe is,and the more obvious the impact of the excitation frequency on the sensitivity of the eddy current probe is.The findings can provide a certain reference for the reasonable determination of excitation frequency and lift-off distance,which provide theoretical guidance for the optimal design of probe structure as well.

关 键 词：涡流检测 探头线圈 几何参数 灵敏度 有限元法 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]